Painting Light: 4 Lighting Types Every Artist Must Know

Light source is the single most important decision you will make when composing a painting — and it is the element I see artists most often overlook.

When I jury shows, I review hundreds of paintings at a time. I see strong drawing skills, confident colour mixing, beautiful shape placement. And yet so many of those paintings fall short. Not because the artist lacks talent, but because they didn’t consider their light source. Mediocre lighting is the quiet demise of more paintings than almost anything else.

In this post, we will look at the importance of light in painting, how to think about value (the relationship between light and dark), and why considering the four main types of lighting can transform your compositions. These are principles I apply to every one of my acrylic paintings — and they apply equally, whatever your medium.

Why Light Is the Most Important Element in Your Painting

We see form, shape, value, texture, and colour because of light. It is light that creates visual interest in a work of art, directing the viewer’s eye around the composition. Without a strong, considered light source, a painting can become flat and lose the viewer’s attention.

It is astonishing how often artists don’t consider light until they are well into a painting. But light is not a finishing touch. It is a foundational decision and needs to be made before the brush touches the canvas.

Step 1: Decide on Your Light Source Before You Begin

The first step when planning a painting is to determine the type of lighting and where it originates. Is it natural light or artificial? Does it come from in front, beside, or from behind? These decisions will shape every other element in your composition — the shadows, the values, the sense of depth, and the overall mood.

Getting this right is the difference between a painting that draws viewers in and one that leaves them feeling unmoved, even if they can’t explain why.

Step 2: Understand Value — Light and Dark in Painting

Once you’ve established your light source, the next step is to plan your value structure. Value in art refers to the relative lightness or darkness of a colour on a scale from white to black.

A successful painting doesn’t need to use the full middle-value range — but it should always include the lightest light and the darkest dark. I would argue that value is more important than colour to the design and success of a piece of artwork. I jury paintings that show strong drawing, good colour mixing, and thoughtful shape placement, yet they fall flat because of poor value arrangement. This is especially true in floral painting, where the temptation to focus on colour can distract from building the strong value structure that makes a painting sing.

When you are composing your next piece, ask yourself: where is my lightest light? Where is my darkest dark? If you can’t answer those questions, your value structure may need more consideration before you pick up your brush.

Step 3: Choose Your Lighting Type

There are four main types of lighting in painting, and understanding each one gives you enormous creative control. Claude Monet’s Haystacks series (painted 1890–91) provides a beautiful real-world example of all four — the same subject, transformed entirely by the direction and quality of light.

Here is how each type works, and what it can do for your compositions.

Front Lighting

In front lighting, the light source is directly behind the viewer and falls squarely on the subject. The result is minimal shadow, flat values, and a limited tonal range.

Front lighting is by far the most commonly used — and the least effective. If you take your photo references with the light behind you, or use your on-camera flash, this is what you get. There is little or no shadow, and shadows are crucial for creating the illusion of form. A subject without shadow looks two-dimensional, no matter how skillfully it is painted.

Front lighting has its uses, but if it is your default setting, it is worth pushing yourself to experiment with something more dramatic.

Form Lighting (Side Lighting)

In side lighting, roughly two-thirds to three-quarters of the subject is illuminated, with the remaining portion falling into shadow. This is the most effective lighting for creating a convincing sense of form and depth.

Because side lighting gives you both the lightest lights and the darkest darks in one composition, it creates the full value range that makes a painting feel three-dimensional. It is the easiest type of lighting to work with, and often the most rewarding. When I am setting up a reference for a new flower painting, side lighting is where I start.

Rim Lighting (Edge Lighting)

In rim lighting, the light source is positioned mostly behind the subject. The subject itself falls largely into shadow, with just a thin rim of light catching one edge.

This is one of the most dramatic lighting conditions available to a painter. Used well, it can give a subject an almost luminous quality. The results can be striking but keep in mind, it does require confidence in creating interesting darks. (See my blog post Why I Paint Without Black (And What I Use Instead).)

Back Lighting

In back lighting, the light source is positioned directly behind the subject, leaving the side facing the viewer largely in shadow. A delicate rim of light often traces the subject’s edges, creating a luminous glow that adds atmosphere, depth, and a sense of quiet drama.

Back lighting is often the most challenging of the four lighting conditions to paint convincingly, but it can produce powerful results. The secret is to resist the temptation to describe every detail. Instead, allow the glowing edges, the dramatic contrast between light and shadow, and the subtle value shifts within the darks to tell the story.

Light Is Where Every Painting Begins

Taking time to consider the light source, the contrast of lights to darks, and the type and direction of light will positively impact your piece. It’s how I begin every composition. You might think that my large-scale floral paintings are all about flowers, but they’re not. They’re all about light.

If you’d like to see how these lighting principles come to life on canvas, I invite you to browse my original flower paintings — every one of them began with light source in mind.

And if you have questions about my process, feel free to send me a message here. Or, if you’re interested in having a painting created for a specific space, I’d love to hear from you on my commissions page.

Laurie Koss is a Canadian contemporary flower artist based in Kelowna, BC, and a Senior Member of the Federation of Canadian Artists (SFCA). Her large-scale acrylic-on-canvas flower paintings have been featured on Canada Post stamps and a Royal Canadian Mint collector coin. She also shares her expertise about light in Episode 8 of her Responding to Art series on YouTube.